So I tried charging for a very long time but the orange light is still blinking which suggests it is not fully charged which is charged given how long it's been charging.

I'm not sure I understand how to "flash the FW"? Would you mind giving me some more details on that or direct towards a relevant source.

I read about it and it seemed to involve using a SD card and so. The issue is that my ebook reader 902 does not connect at all with my computer so it seems impossible to carry out a "software" operation.